Dirty equipment Clean Hold time studies :

Dirty equipment Hold time studies :

Now a days  the auditors are asking about the Dirty equipment Hold time study report in cleaning validation:

What is dirty equipment : 

Uncleaned equipment over a period of time

What is dirty equipment Hold time : 

The time between "after use" and "before cleaning" of equipment.


What to study : 
whether the cleaning process is capable enough to clean the dirty equipment and meets the acceptance criteria.

Plan :

Keep the equipment idle after usage(unload the material) and do not clean for 24 hours. collect the physical traces of sample after 8,12 and 24 hours respectively. then clean the equipment

Check for degradation using related substances method for the samples of 8,12 and 24 hours collected from different locations of the equipment.

Collect and check the rinse/swab sample after 24 hours for the product absence.

Clean hold time studies : 
The time period between "after cleaning and before use" of equipment.

Procedure :
After cleaning of an equipment, keep it idle for 48 hours and check swab sample for microbial counts.
TAMC : 1000 Colony forming units/swab
TYMC : 100 Colony forming units/swab